This invention is an improvement over the existing art for the evaporation or distillation of fluids. It may be used for concentration by removing part of the liquid (as in orange juice), for desalination by condensing the water vapor, or for distillation by separating the various ingredients in the fluid (as in alcohol and water). In all these applications the evaporation (or condensation) of the fluid occurs primarily at the interface between the liquid and its vapor while the needed energy is transmitted from a heat source through the container wall to the liquid and then through the liquid to the interface to support the evaporation.
The basic concept of distillation of sea water or other fluids, with or without vapor compression, is not new. However existing distillation systems require a substantial energy input to heat fluids and drive any compressors. Additionally, there is a substantial temperature gradient per stage which limits the number of stages usable with a given temperature rise or energy input and correspondingly limits the output.
It is an object of the present invention to reduce the power required and accordingly reduce the operating cost of the apparatus.
A further object is to lower the heat resistance of the fluid being evaporated and reduce temperature differentials.
A further object is to supply the energy needed to evaporate the fluid by the condensation of the evaporated vapor.